Manufacturers use formaldehyde in household products ranging from plywood to carpeting to shampoos. As volatile organic compound, formaldehyde turns gaseous at room temperature and releases into the air in a process called off-gassing. Although formaldehyde's long-term effects on health are largely unknown, the Environmental Protection Agency considers the chemical to be a probable carcinogen. High indoor levels can produce throat and eye irritation in sensitive individuals.
Seal composite wood products in your home with spray varnish or urethane. Spray the sealer in even, sweeping motions, overlapping the previous spray path a bit with each pass. Coat all surfaces, including edges, completely. Use multiple light coats.
Dispose of household products that list formaldehyde as an ingredient. Common sources of formaldehyde include nail polish and nail hardeners, cleaners and detergents, fabric softener, adhesives, shampoos and antiperspirants.
Avoid smoking in your home. The Minnesota Department of Health warns that combustibles like tobacco, wood and gas release formaldehyde when they're burned.
Ventilate your home well, especially when you burn wood, gas or other liquid or solid fuel. The burning fuels in your gas oven and stove, wood stove, fireplace and propane space heaters release formaldehyde into the air.
Install vent hoses and pipes from combustible appliances like gas ovens and stoves so that they siphon fumes directly to the outdoors via an opening in an exterior wall. Follow the manufacturer's instructions for proper installation. If your appliances can't be vented directly, purchase a vented range hood for your kitchen and follow the manufacturer's instructions for venting that through the exterior wall. An unvented hood merely moves smoke and fumes around. A vented hood carries them outside of the house.
Keep the air in your home cool and dry. Heat and humidity increase formaldehyde levels. According to the Minnesota Department of Health, formaldehyde is water soluble -- and humidity is water in the air -- and it reacts to temperature increases in such a way that causes household products containing formaldehyde to off-gas more of it than they would in a cooler, drier space.
Wash permanent press clothing and home decor fabrics before you use them. They may contain formaldehyde. Formaldehyde is water soluble so water can rinse it away.
Use exterior-grade pressed-wood products for future indoor projects. Manufacturers use a different type of resin to bind the composite material for outdoor-grade products than they use to bind indoor-grade products. The resin used in outdoor-grade projects emits less formaldehyde.
Keep new rugs, composite-wood furniture and other off-gassing items in a well ventilated garage or shed for several days before you bring them into your home. The storage area must have good air flow so that fresh air moves across the surface of the off-gassing items.